Racquet Acceleration

[NamRanger]

After watching a whole lot of groundstrokes and serves, it seems that pros really don't swing too fast before contact, but they seem to accelerate alot faster when they make contact. Anyone else notice this trend? It's like they are "finding" the ball first before they accelerate through it.



Roddick isn't the best example, but pretty much all pros that I've watched so far have this in common.



http://www.youtube.com/watch?v=V-D32RwsD_w


As you watch Roddick from his backswing to moving the racquet foward, you'll notice the racquet really doesn't take off till slightly before it makes contact with the ball, when the racquet DOES make contact, then it really starts to accelerate, much faster then the racquet's initial foward acceleration into the ball.



Here's a video of Tommy Haas practicing

http://www.youtube.com/watch?v=tDiNRVv_0zU&mode=related&search=


Notice how you can easily track when the racquet is moving foward initially, but when Haas makes contact, the racquet sort of blurs out as he starts accelerating through the ball.

 

[Bagumbawalla]

There is a lot of what I would call anecdotal or even superstitious thinking when it comes to sports. Tennis is one of the most intrenched with mystic explainations and arcana-- secrets the pros know and are kept from ordinary humans-- and if we could steal those secrets (like fire from the gods) we might ascent to the status of pros, ourselves.

Part of the problem is our lack of ability to describe the difficult motions and the inner feelings associated with them. Even good instructors resort to explainations that are not always sound physics. What people think they see, or feel is not always accurate.

Obviously there is acceleration in a tennis stroke, just as in a baseball swing or in golf, cricket, badminton, squash...

The very idea of acceleration is that it accelerates-- gets faster and faster, starting from 0 and accelerating (like a rocket) to 50, 60, miles per hour in a groundstroke.

The best groundstrokes are smooth and flowing. Ther are no sudden changes, shifts in direction or microsecond boosts of speed.

What you may be noticing is that there are, indeed, different types of players who do have different stroking techniques.

Some take a long, full swing that seems to build speed more gradually to its final impact. Others (still smooth and without hitches) will tend to "power" the racket through the ball and the force seems (to the eye) to come all at once and at the last moment.

Many clay court players have the former style, they have more time to be fluid and take a full stroke. Fast court players, or players who hit "on the rise" will tend to the later style. Agassi is a good example of the second type.

The important thing is for you to find a style that fits your physique, your playing surface, your strength and ability level and so forth. More than the discovery of hidden secrets, PRACTICE, consistence, and focusing on the basics while perfecting your technique are the keys to advanciing your game.

Good luck,

B

 

[XhotXEX1290]

Hit the ball and than swipe around your shoulder.

 

[NamRanger]

There is a lot of what I would call anecdotal or even superstitious thinking when it comes to sports. Tennis is one of the most intrenched with mystic explainations and arcana-- secrets the pros know and are kept from ordinary humans-- and if we could steal those secrets (like fire from the gods) we might ascent to the status of pros, ourselves.

Part of the problem is our lack of ability to describe the difficult motions and the inner feelings associated with them. Even good instructors resort to explainations that are not always sound physics. What people think they see, or feel is not always accurate.

Obviously there is acceleration in a tennis stroke, just as in a baseball swing or in golf, cricket, badminton, squash...

The very idea of acceleration is that it accelerates-- gets faster and faster, starting from 0 and accelerating (like a rocket) to 50, 60, miles per hour in a groundstroke.

The best groundstrokes are smooth and flowing. Ther are no sudden changes, shifts in direction or microsecond boosts of speed.

What you may be noticing is that there are, indeed, different types of players who do have different stroking techniques.

Some take a long, full swing that seems to build speed more gradually to its final impact. Others (still smooth and without hitches) will tend to "power" the racket through the ball and the force seems (to the eye) to come all at once and at the last moment.

Many clay court players have the former style, they have more time to be fluid and take a full stroke. Fast court players, or players who hit "on the rise" will tend to the later style. Agassi is a good example of the second type.

The important thing is for you to find a style that fits your physique, your playing surface, your strength and ability level and so forth. More than the discovery of hidden secrets, PRACTICE, consistence, and focusing on the basics while perfecting your technique are the keys to advanciing your game.

Good luck,

B

I've looked at alot of pro strokes in slow motion. They really do not accelerate that fast untill contact, then the racquet explodes through the ball. Even Agassi, who you say "forces" the ball seems to guide his double bend into the ball, then accelerate through. It's almost as though every pro is looking to "hold" the ball, and then "release" by pushing through it.


Because truly, the racquet doesn't move the ball, the player does it. At contact, the wrist stays back along with the racquet, as the player pushes the double bend with his shoulder and waist to lift the ball, thus allowing the player's weight to fully transfer into the ball. That is, if we're talking about modern technique here. So really the racquet doesn't "accelerate" in the way most people think it does.


That's why pros can create so much pace now without a huge backswing. Weight transfer is all you really need to get the ball moving, or so it seems to me.

 

[Bagumbawalla]

If it somehow helps you to visualize the stroke in that manner- and it helps your game, then I wish you all the best. As I said, most inages and descritiptions in tennis are only approximations of reality. Some suggestions work better for some than others.

Having said that, we have, about once a month, someone write on this topic (a shill?). Feel free to click on "search", above and read the general consensus.

Good luck with your game,

B

B

 

[tlm]

You are exactly right namranger, it is what the pro's do with the modern forehand.As far as what bagumbawalla is saying, i dont know what he is talking about.I would like to know how images+desccriptions are only approximations of reality?Reality is exactly what the videos show, the slo mo video of roddick with the windshield wiper forehand is fact not fiction.

Some people here dont want to see it, because this is the way Oscar Wegner describes it+not to many hear want to admit he is right.Plus there are a lot of old school players on this site that were taught to use a continental or eastern grip with early take backs+ flat strokes.I dont think they understand the modern forehand or they dont want to admit it.

Some of the best players i see at my club hit flat with the more conventional strokes+are excellent players, i am not saying that this method doesnt work it can be very effective.But that is not the way the pro's hit, the grips are sw+western with a lot of topspin+ a lot of times with the windshield wiper style follow through.

This is no secret just watch the many videos available, they dont use the old school ways of taking back early+ follow through is not towards the net+ they do not get the racquet moving fast early in the swing like the older players did.I really think that a lot of the instructors on this site cant admit that the game has evolved+it is not the way they have been teaching for years+they cant admit that the new way is better!!!!!!

 

[es-0]

In the Roddick footage it appears to me that the racquet is moving at the same speed throughout the actual stroke, if it appears any faster closer to contact it is due to the fact the racquet is changing orientation so it can strike the ball squarely.

Just my observation...

 

[widmerpool]

i can't think of a pro player in the history of tennis who didn't "accelerate" through every shot.

when you serve, you are at rest, (0). you want to get to maximum speed, (1). So to get from 0 to 1, you accelerate.

same with throwing a baseball, kicking a soccer ball, shooting a puck...

i'd like to know how the "modern" game has improved on the Rosewall backhand.

racquet and string tech has allowed some wiggle room but it's the same game.

 

[TheShaun]

roddick isn't even looking at or anywhere near the ball when he makes contact. wow!

 

[tlm]

Nobody said that they dont accelerate through the swing, but they dont try to get the racquet moving as fast as possible before the contact.The point is they definitely accelerate through the swing, that is what we are saying that most of the speed of the swing is right after contact. Another thing to check out in the roddick video is he is still taking the racquet back after the ball has bounced, in the conventional style of teaching your supposed to get the the racquet back earlier.

Another thing it shows is how roddick lifts up, not towards the net, he actually leaves the ground+his follow through is to the side not forward.Remember being told to stay down on groundstrokes + follow through towards the net, doesnt seem like roddick follows the old school teachings.

You mean to tell me you can watch videos of the old boys + tell me that thier swings look the same? Even watching tennis from the 80's it looks like they are in slomotion+ it is a hell of a lot more than just the strings, it is modern technique.It is not the same game by any means, the women hit the ball harder than the old boys did.

 

[Ross K]

early set up or delayed counting method?

.Plus there are a lot of old school players on this site that were taught to use a continental or eastern grip with early take backs+ flat strokes... This is no secret just watch the many videos available, they dont use the old school ways of taking back early+ follow through is not towards the net+ they do not get the racquet moving fast early in the swing like the older players did.

Are you then saying that modern technique=setting up at the last possible second (ie, NOT being prepared and set up, either on your bh wing or fh side, asap - or as soon as you realise which side incoming ball is coming to)? I do remember Wegner's completely different method of counting in your head after the ball-bounce and delaying the hit (like... "1-2-3-4-HIT!"... something like that?)... is this what you advocate?

 

[tricky]

Here's a video of Tommy Haas practicing

That's one sexy beast. Dang.

I do remember Wegner's completely different method of counting in your head after the ball-bounce and delaying the hit

The funny thing is, I don't necessarily disagree with Wegner on his point. From the little I've read, he's really into cadence and rhythm. In that regard, it makes sense to find a methodical rhythm with the rally.

I don't think Wegner was against setting up the unit turn early. I think he was more concerned with the hitting arm moving out of sync, thereby causing people to mishit or "arm" the shot. But I think if you concentrate on measuring and triggering the stroke with your non-dominant arm, that shouldn't be a problem. His counting would help you do that.

The racquet acceleration stuff is tricky, because what you really want is to have a very, very relaxed backswing. Initially, a very relaxed backswing has to be slow because you're still learning to trace the backswing with your shoulder. But as you get better at recognizing balls and getting a stronger grip, the backswing moves quicker. It'll also grow more compact.

In terms of forward swing acceleration, some of it is a product of a relaxed
wrist laying back, and a lot of it reflects how well you swung out of a "slot." The latter defines the "length" of the line you pull toward the ball. If you got a very long line (which isn't that discernable to the naked eye), you'll get more acceleration.

Verdasco's straight-arm FH is a really good example. He has a relaxed, almost "slow" backswing, and then as he's swinging through the ball, it accelerates and sounds like a cannon. He's also excellent at lifting his whole body toward the ball in classic sit-and-lift fashion.

 

[D-man]

The secret is, that as you accelerate you want to reach the position of the point of contact in such a way that it ends up that your whole upper body is moving as one unit to push the ball. The idea of acceleration can confuse you into trying to accelerate parts of your body out of sync with the upper torso as a whole, particularly the three hinges that connect the ball to the main moving mass of the torso, which should be the source of power (the wrist, the elbow, and the shoulder are the hinges). Thus although at times the parts in-between the hinges may be moving/accelerating at different speeds, they synchronize at the point of contact and the body takes over virtually "pushing" the ball from the waist. This is why timing is such a big part of strokes and makes them tricky to learn. But it's when you lose sight of the goal that you get lost in a sea of complexities. To put it as succinctly as possibly, emphasizing racket-head speed can cause you to lose sight of the fact that the whole upper body powers the ball; better to call it "upper-body speed."

Watch the Roddick forehand video above and contemplate as it progresses how various parts get moving such that at contact everything is pushing together as one unit. I, personally, do not believe in some magical "super-acceleration" at the very moment of contact, and though I do think that there is a significant degree of acceleration just before contact, I think it also must be considered in the context of one smooth overall progression followed by the deceleration.

I also see four main ideas from which the body push is developed. One is momentum transfer such that all energy is transferred from the inside out, leading to number two: energy travels internally to externally, emphasizing internal body rotation, because for the body to push out one way it has to collapse back the alternate way, and the third is the idea of keeping a fixed structure in the upper body so that energy and directional control is not diluted. The third is why you almost always see the shoulders constantly kept in a straight line. The fourth is synchronization at contact, which I just explained. All of these ideas keep you from trying to add power through a quick movement of a hinge (wrist/elbow/shoulder) which only dilutes power, hurts the joints, and loses control.

 

[origmarm]

I came to a very similar conclusion as the OP having watched Roddick in particular recently. Having thought about it a fair bit however I think its a form of "optical illusion" if you will that gives this impression of last minute acceleration.
Personally I think its similar to what D-Man is describing here in that the swing is actually a gradual smooth acceleration but that the rest of the body has also got to full acceleration just before the point of contact. When the rest of the body reaches this point it gives the impression of a sudden acceleration to the swing. I also thing that the wrist changes the angle also at that point further reinforcing this. So its not the fact that he suddenly accelerates the swing, just everything else gets in on the act at that point

 

[Go Tennis]

You increase acelleration BEFORE the contact with the ball JUST THINKING TO HIT THE BALL WITH MORE ACCELERATION. And don't forget to find the distance to the ball, then swing relax, but fast and without hesitation. When you play tennis your mind need to be 110% thinking in every step of your attitude in court. You ONLY relax your mind when the ball is out.
Tip: Doing what I said above, you will ALWAYS look at the ball until the contact.

 

[tlm]

Ross K, i never said anything about setting up at the last second,you should set up as quickly as possible.In the video of roddick it is obvious he is set up early, that is one of the points he has plenty of time+ he is set up but his swing is not going all the way back untill after the bounce, which i have been told many times here that the pro's never do that.

Even though there are many videos just like this one showing that exact thing.The swing is timed so it is one fluid motion+ it is not an optical illusion that the racquet is started slow+accellerates more right at+ after contact.What is so hard to understand about this? Do you not trust your own eyes?

 

[origmarm]

Even though there are many videos just like this one showing that exact thing.The swing is timed so it is one fluid motion+ it is not an optical illusion that the racquet is started slow+accellerates more right at+ after contact.What is so hard to understand about this? Do you not trust your own eyes?

Sorry, reading that again I wasn't clear at all. I think the racquet head does indeed accelerate and is clearly moving faster, I just don't think its a result of the swing portion of the stroke i.e. I think he is exerting the same pressure through his arm for the entirety of the swing but the addition of other portions of his body to the motion produces the acceleration of the head

 

[Narcissist]

Maybe this analysis of Ivanovic's forehand might hold some answers:

http://www.tennisclip.com/media/106/Ana_Ivanovic__Skeletal_Analysis__Forehand/

If I remember there is a trace of her raquet path with the colour matching racquet speed and stuff like that.

I'm no expert but in slo-mos *some* pros look like they suddenly whip the wrist through causing big acceleration a bit like the wrist snap on serve.

 

[Ross K]

Ross K, i never said anything about setting up at the last second,you should set up as quickly as possible.In the video of roddick it is obvious he is set up early, that is one of the points he has plenty of time+ he is set up but his swing is not going all the way back untill after the bounce, which i have been told many times here that the pro's never do that.

Even though there are many videos just like this one showing that exact thing.The swing is timed so it is one fluid motion+ it is not an optical illusion that the racquet is started slow+accellerates more right at+ after contact.What is so hard to understand about this? Do you not trust your own eyes?

Yo, chill, matey. All I did was ask a question!?...

 

[kimizz]

This is for the OP. Im not sure if I understood your point clearly. This is how I understood it. You sayd the racquet really takes off just a bit before contact and continues this rapid movement after contact. Meaning that the the racquet acceleration happens very late.

Isnt this exactly what B-bill talks about when he writes about the role of elbow. Meaning that the elbow leads the forward swing for a while, after that the racquet gets in front of the body in a whippy motion. The racquet definetly accelerates just before contact but it isnt a deliberate action by the player...its just the racquet following the elbow. Maybe someone can explain it better, writing in english is really hard :sad:

To TLM, who are these old school instructors in this site. I think I have a modern forehand and its all thanks to the ppl that post their tips to TW.

 

[tricky]

Meaning that the elbow leads the forward swing for a while, after that the racquet gets in front of the body in a whippy motion.

That's exactly it. That period is the "acceleration" stage of the forward swing, when the butt cap is facing or has established a line toward the ball.

 

[The Gorilla]

perhaps you reach the greatest acceleration immediately after putting your full effort into it and begin slowing down afterwards, that's the only explanation I can come up with as to why this would work any better.

 

[JohnYandell]

One fact to consider is that 3D analysis has established that the fastest point in the swing is almost always right at the contact.

This has been measured, by Bruce Elliot, Greg Ryan, Brian Gordon.

The motions are smooth and continuous, but the biggest increases in the speed are in the few microseconds just before contact.

Everything else after is deceleration. Not that you would necessarily try to decelerate after contact, however.

I used to believe that that the acceleration continued out into the followthrough and it may feel like that, but it's not the actual reality.

The facts may be different than what players or coaches think, or even from what makes them actually happen in the right sequence.

So we need to distinguish reality from the teaching ideas, phrases, and images that produce it. They may be the same, but they may also be different. But let's not confuse one with the other.

 

[kimizz]

One fact to consider is that 3D analysis has established that the fastest point in the swing is almost always right at the contact.

This has been measured, by Bruce Elliot, Greg Ryan, Brian Gordon.

The motions are smooth and continuous, but the biggest increases in the speed are in the few microseconds just before contact.

Everything else after is deceleration. Not that you would necessarily try to decelerate after contact, however.

I used to believe that that the acceleration continued out into the followthrough and it may feel like that, but it's not the actual reality.

The facts may be different than what players or coaches think, or even from what makes them actually happen in the right sequence.

So we need to distinguish reality from the teaching ideas, phrases, and images that produce it. They may be the same, but they may also be different. But let's not confuse one with the other.

Nice to hear you view on this. To me it makes sense that the acceleration is not continuing after contact...it kind of feels like a lot of energy is gone after contact.

 

[fgs]

it can surely happen that you accelerate right after contact point - but then it is a mistimed stroke and you should be going through some proper drills to get that right. after all you want to transfer the energy to the ball and not waste it.
i think that bagumbawalla was addressing the fact that videos can be misleading. i play tennis for quite a while now and have done video analysis some 25 years ago as i also do currently. the point to this whole video stuff is that depending on what you want to show to the player you simply have to use diffenrent angles. the roddick video is misleading regarding acceleration after the point of impact simply because you will see his wrist going lose and the racquethead apparently getting faster after impact. the angle is also misleading, since you are already in a almost 90degrees angle to the camera, so you cannot judge acceleration anymore, as you wouldn't be ablte to do on the foreward motion if the camera would have been positioned in front or behind the player.
both, roddick and haas point to the back of the court on their backswing, so if that is compact, than i'm from outerspace.
next, i think roddick is going for a winner on that shot because he is definitely inside the court. therefore he also "takes a jump" at the ball in order to put more weight into it. now, we have to clearly separate things - we are talking about a competitive player, and i can tell you that these kind of "jump at the ball shots" have been around some 30 years ago as well, but it's just a technique you don't teach beginners! this is something you start working on with more advanced players already having attended some tournaments and needing to develop or refine a weapon. you also jump into backhands nowadays as you did 30 years ago!
when you start someone up, be it a 5 year old kid or an adult of whatever age, you don't go with roddick-kind killer shots or safin's jumped at backhand. you just try to get that person keep their feet on the ground and try to develop a sense and feel of the striking motion. if the person got any feel for the ball, than a long journey begins that is hopefully one filled with fun.

 

[tlm]

It makes sense that acceleration is not continuing after contact? You bring the racquet to the ball + some say the fastest part is right at contact.What happens then, the racquet instantly slows down?

It would seem that after the weight of the ball is gone the racquet would naturally speed up, you cant just stop this momentum.I dont care if it a baseball swing, a golf swing or a tennis swing the fastest part of the swing is right after contact.

During matches on tv sometimes they will show one of the pro's forehands in slomotion+ the speed looks pretty steady until after contact then the racquet becomes a blur.Is this because the racquet is slowing down?

As far as fgs points,you say the video shows the racquet head apparently getting faster after contact.There are many more videos that will show that the racquet is getting faster after contact, has nothing to do with the camera angle.

I dont know if roddick is going for a winner or not but he does have time to set up.Most of the time when the pros have some time they take this kind of a swing.I dont believe he is taking a jump at the ball though, he is rising up + leaving the ground for rotation, which is were he gets most of the power.

I dont think the pros jump into shots very often, they do rise up, not forward very much that is one of the main points.The racquet comes to the ball at a steady rate+then right at contact they get tremendous rotation into the ball+ that is why the swing is so fast after contact.They put a huge amount of energy at the last second into the ball.That is also why the racquet is moving the fastest after contact.

 

[fgs]

tlm,
there is one thing you seem to have decided to ignore - that is the point of impact. the darn ball comes with some speed with just the opposite direction as the racquet is moving. now, the racquet is accelerated and on the point of hitting the ball it slows down for those 4-5 miliseconds that make up for the socalled dwelling time. then it takes off and and there is no more opposing force on the racquet-player combo, so you think that the player is accelerating.
next point you decided to ignore is the simple fact that acceleration as well as deceleration ar no instant processes. therefore you have a shorter or longer backswing in order to provide room for acceleration until impact and have a followthrough for deceleration.
i'm not that good at judging spaces on videos, but besides the fact that roddick turns to the left to decelerate his body rotation, he also moves forward (i said jumps) about a foot (30cm).
there is a sequence of movements called the kinetic chain that provides for the power in strokes, it all starts with the loading of the legs (to emply the socalled ground reaction forces), moves through the lower body, upper body and so on. there is absolutely no secret in what roddick is doing, it is well documented in books and pictures for more than 20 years and part of any decent tennis instructor curriculum. but once again i have to say that these techniques are for advanced players.

 

[tlm]

fgs,
i never decided to ignore anything, i dont remember anyone making the point about the impact slowing the racquet down at contact.But what you are saying makes sense that the contact would slo down the racquet for a few miliseconds. I would agree with that, but then you say i think that because there is no opposing force that the racquet takes off+ accelerates, that is correct it only makes sense that this would happen.

Were do i ignore that acceleration+deceleration are no instant process? Just the opposite, i am saying that the racquet is coming at the ball at a steady rate+ then the kinetic chain as you put it puts the power into the ball.This is a combination of the racquet coming forward, the rotation of the body, all of these things get power into the shot.

I also make the point that the follow through takes time to decelerate the racquet, so i dont know were you came up with this.One of the reasons it takes time is because of all this momentum that is built up.

I still dont see were you are saying roddick jumps into the shot, his right foot moves forward some because of the rotation.If you watch, the left foot also moves back.I would say it is obvious that rotation is why the feet move not because he is jumping into the shot.

I never said that this wasnt more of an advanced technique, but you say that this well documented for 20 years + part of any decent instructors curriculum? I have no idea if that is the case, but i dont seem to recall seeing that kind of a forehand from many of the old time players.

 

[fgs]

tlm,
i didn't mean to be offensive and i'm truly sorry if you got it that way.
i assumed it is obvius that in the moment of collision there would be a temporary slowdown in the racquetswing which after the ball leaves would pick up (some) of its initial speed again, but this being already part of the followthrough and not in the acceleration path anymore. i'm glad you agree with this.
modern technique definitely implies more body rotation, but this thing basically started with bjorn borg and heavy topspin tennis, and that's some 30 years ago already (time is a b i t c h ). i just had a chance to watch one of his wimby finals against mac, and both players (with very different techniques) had quite a lot of "air time". borg was jumping more into his forehands while jmac into his backhands.
regarding the curriculum - i have just recently updated myself with most of the itf books (i'm starting up my son and i don't want to teach him obsolete techniques), just to find out that not much has changed from what i have been taught. as funny as it seems, we had some western grippers 30 years ago too, but i stayed with eastern. i remember having a complex drill which included an approach shot where our coach had us jump at the ball. the reasoning was to both have more weight behind the shot and by being able to hit it at a higher level, to really shoot it down (i'm sure you understand what i'm talking about). same technique employed on the halfcourt balls you had to go for a winner (if the opponent managed to retrieve the ball we had to do 5 pushups ).

 

[tlm]

No problem fgs, i know that borg did use heavy topspin back in the day.And i am sure there were some western grippers back then, but now it is sw or western pretty much all the way.As opposed to a few like it was in the past, i really feel the forehand has changed a lot in modern times.

That is one of the reasons serve+volley is tough to use at the pro level, these guys can hit tremendous passing shots from anywhere on the court.I know many will say that it is the racquets + strings, which is part of it no doubt.But i really believe that the forehand has really improved from the days of the eastern grip+flatter strokes.

 

[fgs]

tlm,
borg was heavy topspin but with eastern grips. but take courier for instance, he started out in the late 70s i assume (since being born in 1970) and he had full western grips if my memory serves me right. so this technique is not new, but i agree that today it is predominant. there is a trend to more sw currently (i have set up my son like this) which i find will provide for some more variety in the game in the near future. we already see the likes of djokovic and murray, being able to play power shots but also some nice dropshots and angles.
the days of the eastern grips + flatter strokes are mostly gone by for a simple reason: with the current speed of the game (and it has been slowed down by the changes in balls and surfaces!) you will not hit the ball within the lines unless you spin it (obviously i mean offensive shots, because you see lots of slices as defense). a flat hitter like 30-40 years ago would have no chance in todays competitive environment. also, it was quite difficult to generate a lot of headspeed with those 400-420g racquets i have played in my junior days. graphite changed things by lowering the weight, besides bringing more power by means of stiffer frames. so racquet head speed got ever more important as a means to not only play a fast ball but rather getting the ball under control.

 

[JohnYandell]

It's fascinating to observe the acceleration and deceleration patterns in the strokes.

The question that arises is: how can a player create a swing pattern which optimizes this?

I think the answer has little to do with the actual mph at any point in the swing. It has to do with achieving the key positions, especially in the coiling or preparation and the finish.

If a player understands these elements and passes thru the positions associated with the great strokes for a given grip style and given ball, the acceleration more or less takes care of itself.

I see a lot of players doing things that are artificial trying to "accelerate" the racket. I think that the speed of the racket is a consequence of a well-executed biomechanical motion that involves the entire body.

 

[fgs]

john yandell,
you are perfectly right. the "only" trouble is that one has to relate this perfect biomechanical motion to a incoming ball, which has the bad habit of coming in at different angles, spins, speeds, depths etc.
when the timing is "off" one ends up with these "artificial" movements you talk about. while you still can get good racquet speed while swinging wildly at the ball, the control part of the game gas gone for a coffee-break.

 

[tlm]

I couldnt agree more john, if i think of trying to accelerate at a certain part of the swing it does not work well.But trying to set up well+ using the motion smoothly works much better.

A couple of years ago my wife filmed me + a friend while we were hitting back+forth. I was surprised that my racquet would go up but then end up pointing down on the follow through.I was using a windshield wiper motion + didnt even know it until i filmed my swings.

I guess it was part because of a strong sw grip+ i was really trying to put extra topspin on the ball.But if i try to hard to think about putting that motion on the ball it doesnt work near as well as just trying to set up good + take my normal cut at the ball.

 

[kimizz]

It makes sense that acceleration is not continuing after contact? You bring the racquet to the ball + some say the fastest part is right at contact.What happens then, the racquet instantly slows down?

No it doesnt instantly slow down...the swing is so fast that there is a lot of speed in the follow through also. BUT to me it makes sense that the speed is slowing down after contact. And thats because I feel like a lot of energy is gone after I hit the ball.

 

[The Gorilla]

watching tim and fgs trying to ingratiate themselves with johnyandell is so childish and undignified it's hard to read.

 

[fgs]

the gorilla,
i simply don't get your point, could you please explain. it could be my lack of understanding since i'm not a native speaker, so please go to the trouble and spare the time to explain how i ingratiate myself along with tlm in regard to johnyandell. thank you.

 

[The Gorilla]

you are both appealing to his authority, both are sucking up, and despite the fact that both of you have completely different views, you both begin by saying that you couldn't agree more with yandell's analysis

 

[widmerpool]

maybe a physicist could chime in, but...

how could the *racquet face* accelerate after the impact of the ball???

the most speed is necessarily moments before impact.

the ball is going to absolutely crush the racquet face no matter how perfect the stroke is.

yes, the racquet face will speed up again after impact but it can't reach the same speed as pre-impact. plus, you'd better start decelerating quickly unless you want to have the racquet fly out of your hand or wrap around into your rib cage.

 

[fgs]

the gorilla,
first - thank you for explaining. BUT then please go on - please educate me: how is john yandell and where does his authority come from. i really don't know anything else but that he has been a poster in this thread. (i'm honestly not kidding!!!).
next, i did only partly agree with him. maybe i did not express myself correctly. this is the way i see it: as long as we are talking pure biomechanics he is absolutely right about those swing things - his points are backed up with lots of literature i have recently gone through (itf books). i "dared" relativate his sayings as we are here talking about playing tennis and not ballet. so you have to keep this swing stuff right IN RELATION TO THE INCOMING BALL. if we were to shadow strokes, the vast majority of players having gone beyond beginners status would simply do it right by imagining the incoming ball. as soon as we get to the practical side of things, the frequency of timing mistakes will tell our real value.
next point regarding tlm vs. fgs - he initially said that the racquet would be fastest after impact. i told him that this is an optical illusion (probably the roddick video didn''t have enough frames per sec.) and that he ignores the moment of impact, when the racquet is slowed down considerably due to the collision, just to "reaccelerate" after the force has been transmitted to the ball. but this happens already in the deceleration phase of the players kinetic chain and therefore it is an optical illusion. tlm agreed on this point.
so what are we sucking up? i thank you in advance for your time you take to reply to my post.

 

[JCo872]

After watching a whole lot of groundstrokes and serves, it seems that pros really don't swing too fast before contact, but they seem to accelerate alot faster when they make contact. Anyone else notice this trend? It's like they are "finding" the ball first before they accelerate through it.



Roddick isn't the best example, but pretty much all pros that I've watched so far have this in common.



http://www.youtube.com/watch?v=V-D32RwsD_w


As you watch Roddick from his backswing to moving the racquet foward, you'll notice the racquet really doesn't take off till slightly before it makes contact with the ball, when the racquet DOES make contact, then it really starts to accelerate, much faster then the racquet's initial foward acceleration into the ball.



Here's a video of Tommy Haas practicing

http://www.youtube.com/watch?v=tDiNRVv_0zU&mode=related&search=


Notice how you can easily track when the racquet is moving foward initially, but when Haas makes contact, the racquet sort of blurs out as he starts accelerating through the ball.

Great observations!

Here is my take on this. So much power comes from contacting the ball well in front of the body with your body and hand properly positioned behind the ball. It's what pro strokes all have in common. I think this can be explained by the physics of spring.

When we watch high speed clips of pro strokes, we see the ball compress deep into the string bed and spring away. This spring event is maximized when the racket is in front of the body (leverage) and the hand and body are properly positioned behind the racket for support.

If you accelerate your arm and racket early, the arm and racket start to come across the body right away. You don't get the clean contact point in front of the body. Instead you get a swiping action. This is what I see on most tennis courts. Circular, fast swings around the body.

If you want to see a perfect contact point, pause the Federer clip on my homepage on contact. Watch how his arm is straight and the shoulder and hand are properly positioned behind the ball. He is getting maximum leverage and maximum support behind the racket for the ball to compress and spring away.

Try taking your arm and racket back and "swing fast" at the ball. Your arm and racket will never get into the position Federer is in. Instead you have to use upper body rotation and a lifting motion from the arm to achieve this kind of contact point.

If you watch Federer come into contact in that video, you will see his entire arm lift upwards, like he is bowling a bowling ball. This lifting motion, as opposed to a swinging motion, is what lets him get such a perfect contact point in front of his body. What you see today is lifting motions and pulling motions and rotating motions to acheive solid contact points in front of the body. You don't see "swings".

For another example, check out my clip of Verdasco:
http://www.hi-techtennis.com/video_sample/index.php?movie=verdasco_forehand_001.swf&size=wide

Watch how he achieves such an amazing contact point with a straight arm and the strings flat on the ball. He doesn't do it by "swinging fast" into contact. All he does is rotate his upper body and lift his hitting arm to achieve a pro level contact point.

If you really want to spring in action, with leverage and body/support at work, check this out. Watch how the player almost "pushes" through the ball rather than "swings fast" at it:
http://www.hi-techtennis.com/forehand/flash/spring.swf

Jeff

 

[tlm]

the gorilla,
whatever you say gorilla, i did not agree with the first points john posted.But the last post made great sense, i thought he was right on the money.So you can say whatever, but when someone makes a good point i will recognize it.On top of that i did experience exactly what he was saying.

I have had some heated debates with john in the past and one thing about him is he would still answer questions from me, even though we had are differences.Maybe you should check out some past posts+ see how much i was sucking up to him gorilla.

 

[chess9]

I suspect that in the vast majority of impacts between racquet and ball, even at the pro level, the racquet starts decelerating upon impact. This is simple physics. To overcome the force of the ball (M x A), the acceleration at the point of impact would have to be greater than the sum of the racquet/arm force (M x A) + the force of the ball (M x A). Again, this strikes me as simple physics.

I'm sure someone has done these measurements and calculations.

-Robert